• Title/Summary/Keyword: concrete creep and shrinkage

Search Result 284, Processing Time 0.021 seconds

System Development for Analysis and Compensation of Column Shortening of Reinforced Concrete Tell Buildings (철근콘크리트 고층건물 기둥의 부등축소량 해석 및 보정을 위한 시스템 개발)

  • 김선영;김진근;김원중
    • Journal of the Korea Concrete Institute
    • /
    • v.14 no.3
    • /
    • pp.291-298
    • /
    • 2002
  • Recently, construction of reinforced concrete tall buildings is widely increased according to the improvement of material quality and design technology. Therefore, differential shortenings of columns due to elastic, creep, and shrinkage have been an important issue. But it has been neglected to predict the Inelastic behavior of RC structures even though those deformations make a serious problem on the partition wall, external cladding, duct, etc. In this paper, analysis system for prediction and compensation of the differential column shortenings considering time-dependent deformations and construction sequence is developed using the objected-oriented technique. Developed analysis system considers the construction sequence, especially time-dependent deformation in early days, and is composed of input module, database module, database store module, analysis module, and analysis result generation module. Graphic user interface(GUI) is supported for user's convenience. After performing the analysis, the output results like deflections and member forces according to the time can be observed in the generation module using the graphic diagram, table, and chart supported by the integrated environment.

Analysis on Long Term Behavior in 120-Story High-Rise Buildings according to Lateral-Load-Resisting Systems (120층 규모 초고층 건물에 대한 횡력저항시스템 적용에 따른 장기거동 분석)

  • Kim, Gyeong-Chan;Kim, Jae-Yo
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.35 no.2
    • /
    • pp.119-129
    • /
    • 2022
  • It is essential to control the lateral displacement and differential axial shortening of the vertical elements in high-rise buildings. The differential axial shortening can cause challenges in the serviceability and safety of non-structural and structural elements, respectively. Hence, in this study, the differential axial shortening of the vertical elements and effects of long term behaviors of concrete are analyzed in 120-story high-rise buildings via the construction sequence analysis. Consequently, the axial shortening of the vertical elements is classified into elastic, creep, and shrinkage shortening, and dominant factors to the maximum axial shortening are analyzed. In addition, the serviceability of the non -structural elements is checked with a differential axial shortening at 30 years after completion of construction, and member forces at design and construction stages in girders and outrigger walls are compared.

An Experimental Study on Mechanic properties of Hardened Fly-ash (플라이애쉬 경화체의 역학적 특성에 관한 실험적 연구)

  • Jo, Byung-Wan;Kim, Yeung-Jin;Park, Jong-Bin
    • Proceedings of the Korean Institute of Resources Recycling Conference
    • /
    • 2003.10a
    • /
    • pp.134-138
    • /
    • 2003
  • The purpose of this paper is to recycle the fly ash to the valuable resources and settle environment problems which was caused by the fly ash produced from the thermal power plant. Making the fly ash-cement matrix reused fly ash in large quantities, we looked into minutely the physical properties - the elastic modulus, the compressive strength - to increase the usefulness as the building materials for the structure widely. In this paper, the variables are the water-binder(39, 42, 45%), the fine aggregate ratio(37, 41, 45%). Because the fracture energy is influenced by the strength, it is showed to decrease with the increase of W/B and S/a. Besides, we will be able to know that basic properties of the fly ash-cement matrix are similar to that of concrete. But, it is needed to carry out durability experiment on the drying shrinkage, creep, freezing and thawing test to use structural materials.

  • PDF

An Application of Construction Sequence Analysis for Checking Structural Stability of High-Rise Building under Construction (초고층 건물의 시공 중 구조적 안정성 검토를 위한 시공단계해석의 적용)

  • Eom, Tae-Sung;Kim, Jae-Yo
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.22 no.3
    • /
    • pp.211-221
    • /
    • 2009
  • With recent trends of super-tallness, atypical plan shapes and zoning constructions in high-rise buildings, a structural stability of the building under construction is arising as a key issue for design and construction plan. To ensure the structural stability under construction, the differential column shortening of vertical members, the lateral displacement of tower frames, and differential settlement of raft foundation by unbalanced distributions of a tower self-weight before the completion of a lateral load resisting system should be checked by construction sequence analysis, which should be performed by systematic combinations with structural health monitoring, construction compensation program, and construction panning. This paper presents the scheme of zone-based construction sequence analysis by using the existing commercial analysis program, to check the stability of high-rise building under construction. This scheme is applied to 3-dimensional structural analysis for a real high-rise building under construction. The analysis includes real construction zoning plans and schedules as well as creep and shrinkage effects and time-dependent properties of concrete. The simplified construction sequence and assumed material properties were continuously updated with the change on construction schedule and correlations with in-situ measurement data.